sin^3t的积分的原函数用哪种办法来解?

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sin^3t的积分的原函数用哪种办法来解?
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sin^3t的积分的原函数用哪种办法来解?
sin^3t的积分的原函数用哪种办法来解?

sin^3t的积分的原函数用哪种办法来解?
∫(0->π/2) sin^3t dt
=-∫(0->π/2)sin^2tdcost
=-∫(0->π/2)(1-cos^2t)dcost
=-∫(0->π/2)dcost+∫(0->π/2)cos^2t dcost
=-cost|(0->π/2)+cos^3t/3 |(0->π/2)
=-(0-1)+(0-1/3)
=1-1/3
=2/3

sin^3tdt
=-sin^2tdcost
=(cos^2t-1)dcost
然后积分就可以了